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Diffstat (limited to 'lib/lufa/Bootloaders/MassStorage/Lib/VirtualFAT.c')
| -rw-r--r-- | lib/lufa/Bootloaders/MassStorage/Lib/VirtualFAT.c | 482 |
1 files changed, 482 insertions, 0 deletions
diff --git a/lib/lufa/Bootloaders/MassStorage/Lib/VirtualFAT.c b/lib/lufa/Bootloaders/MassStorage/Lib/VirtualFAT.c new file mode 100644 index 000000000..ffd453128 --- /dev/null +++ b/lib/lufa/Bootloaders/MassStorage/Lib/VirtualFAT.c @@ -0,0 +1,482 @@ +/* + LUFA Library + Copyright (C) Dean Camera, 2017. + + dean [at] fourwalledcubicle [dot] com + www.lufa-lib.org +*/ + +/* + Copyright 2017 Dean Camera (dean [at] fourwalledcubicle [dot] com) + + Permission to use, copy, modify, distribute, and sell this + software and its documentation for any purpose is hereby granted + without fee, provided that the above copyright notice appear in + all copies and that both that the copyright notice and this + permission notice and warranty disclaimer appear in supporting + documentation, and that the name of the author not be used in + advertising or publicity pertaining to distribution of the + software without specific, written prior permission. + + The author disclaims all warranties with regard to this + software, including all implied warranties of merchantability + and fitness. In no event shall the author be liable for any + special, indirect or consequential damages or any damages + whatsoever resulting from loss of use, data or profits, whether + in an action of contract, negligence or other tortious action, + arising out of or in connection with the use or performance of + this software. +*/ + +/** \file + * + * Virtualized FAT12 filesystem implementation, to perform self-programming + * in response to read and write requests to the virtual filesystem by the + * host PC. + */ + +#define INCLUDE_FROM_VIRTUAL_FAT_C +#include "VirtualFAT.h" + +/** FAT filesystem boot sector block, must be the first sector on the physical + * disk so that the host can identify the presence of a FAT filesystem. This + * block is truncated; normally a large bootstrap section is located near the + * end of the block for booting purposes however as this is not meant to be a + * bootable disk it is omitted for space reasons. + * + * \note When returning the boot block to the host, the magic signature 0xAA55 + * must be added to the very end of the block to identify it as a boot + * block. + */ +static const FATBootBlock_t BootBlock = + { + .Bootstrap = {0xEB, 0x3C, 0x90}, + .Description = "mkdosfs", + .SectorSize = SECTOR_SIZE_BYTES, + .SectorsPerCluster = SECTOR_PER_CLUSTER, + .ReservedSectors = 1, + .FATCopies = 2, + .RootDirectoryEntries = (SECTOR_SIZE_BYTES / sizeof(FATDirectoryEntry_t)), + .TotalSectors16 = LUN_MEDIA_BLOCKS, + .MediaDescriptor = 0xF8, + .SectorsPerFAT = 1, + .SectorsPerTrack = (LUN_MEDIA_BLOCKS % 64), + .Heads = (LUN_MEDIA_BLOCKS / 64), + .HiddenSectors = 0, + .TotalSectors32 = 0, + .PhysicalDriveNum = 0, + .ExtendedBootRecordSig = 0x29, + .VolumeSerialNumber = 0x12345678, + .VolumeLabel = "LUFA BOOT ", + .FilesystemIdentifier = "FAT12 ", + }; + +/** FAT 8.3 style directory entry, for the virtual FLASH contents file. */ +static FATDirectoryEntry_t FirmwareFileEntries[] = + { + /* Root volume label entry; disk label is contained in the Filename and + * Extension fields (concatenated) with a special attribute flag - other + * fields are ignored. Should be the same as the label in the boot block. + */ + [DISK_FILE_ENTRY_VolumeID] = + { + .MSDOS_Directory = + { + .Name = "LUFA BOOT ", + .Attributes = FAT_FLAG_VOLUME_NAME, + .Reserved = {0}, + .CreationTime = 0, + .CreationDate = 0, + .StartingCluster = 0, + .Reserved2 = 0, + } + }, + + /* VFAT Long File Name entry for the virtual firmware file; required to + * prevent corruption from systems that are unable to detect the device + * as being a legacy MSDOS style FAT12 volume. */ + [DISK_FILE_ENTRY_FLASH_LFN] = + { + .VFAT_LongFileName = + { + .Ordinal = 1 | FAT_ORDINAL_LAST_ENTRY, + .Attribute = FAT_FLAG_LONG_FILE_NAME, + .Reserved1 = 0, + .Reserved2 = 0, + + .Checksum = FAT_CHECKSUM('F','L','A','S','H',' ',' ',' ','B','I','N'), + + .Unicode1 = 'F', + .Unicode2 = 'L', + .Unicode3 = 'A', + .Unicode4 = 'S', + .Unicode5 = 'H', + .Unicode6 = '.', + .Unicode7 = 'B', + .Unicode8 = 'I', + .Unicode9 = 'N', + .Unicode10 = 0, + .Unicode11 = 0, + .Unicode12 = 0, + .Unicode13 = 0, + } + }, + + /* MSDOS file entry for the virtual Firmware image. */ + [DISK_FILE_ENTRY_FLASH_MSDOS] = + { + .MSDOS_File = + { + .Filename = "FLASH ", + .Extension = "BIN", + .Attributes = 0, + .Reserved = {0}, + .CreationTime = FAT_TIME(1, 1, 0), + .CreationDate = FAT_DATE(14, 2, 1989), + .StartingCluster = 2, + .FileSizeBytes = FLASH_FILE_SIZE_BYTES, + } + }, + + [DISK_FILE_ENTRY_EEPROM_LFN] = + { + .VFAT_LongFileName = + { + .Ordinal = 1 | FAT_ORDINAL_LAST_ENTRY, + .Attribute = FAT_FLAG_LONG_FILE_NAME, + .Reserved1 = 0, + .Reserved2 = 0, + + .Checksum = FAT_CHECKSUM('E','E','P','R','O','M',' ',' ','B','I','N'), + + .Unicode1 = 'E', + .Unicode2 = 'E', + .Unicode3 = 'P', + .Unicode4 = 'R', + .Unicode5 = 'O', + .Unicode6 = 'M', + .Unicode7 = '.', + .Unicode8 = 'B', + .Unicode9 = 'I', + .Unicode10 = 'N', + .Unicode11 = 0, + .Unicode12 = 0, + .Unicode13 = 0, + } + }, + + [DISK_FILE_ENTRY_EEPROM_MSDOS] = + { + .MSDOS_File = + { + .Filename = "EEPROM ", + .Extension = "BIN", + .Attributes = 0, + .Reserved = {0}, + .CreationTime = FAT_TIME(1, 1, 0), + .CreationDate = FAT_DATE(14, 2, 1989), + .StartingCluster = 2 + FILE_CLUSTERS(FLASH_FILE_SIZE_BYTES), + .FileSizeBytes = EEPROM_FILE_SIZE_BYTES, + } + }, + }; + +/** Starting cluster of the virtual FLASH.BIN file on disk, tracked so that the + * offset from the start of the data sector can be determined. On Windows + * systems files are usually replaced using the original file's disk clusters, + * while Linux appears to overwrite with an offset which must be compensated for. + */ +static const uint16_t* FLASHFileStartCluster = &FirmwareFileEntries[DISK_FILE_ENTRY_FLASH_MSDOS].MSDOS_File.StartingCluster; + +/** Starting cluster of the virtual EEPROM.BIN file on disk, tracked so that the + * offset from the start of the data sector can be determined. On Windows + * systems files are usually replaced using the original file's disk clusters, + * while Linux appears to overwrite with an offset which must be compensated for. + */ +static const uint16_t* EEPROMFileStartCluster = &FirmwareFileEntries[DISK_FILE_ENTRY_EEPROM_MSDOS].MSDOS_File.StartingCluster; + +/** Reads a byte of EEPROM out from the EEPROM memory space. + * + * \note This function is required as the avr-libc EEPROM functions do not cope + * with linker relaxations, and a jump longer than 4K of FLASH on the + * larger USB AVRs will break the linker. This function is marked as + * never inlinable and placed into the normal text segment so that the + * call to the EEPROM function will be short even if the AUX boot section + * is used. + * + * \param[in] Address Address of the EEPROM location to read from + * + * \return Read byte of EEPROM data. + */ +static uint8_t ReadEEPROMByte(const uint8_t* const Address) +{ + return eeprom_read_byte(Address); +} + +/** Writes a byte of EEPROM out to the EEPROM memory space. + * + * \note This function is required as the avr-libc EEPROM functions do not cope + * with linker relaxations, and a jump longer than 4K of FLASH on the + * larger USB AVRs will break the linker. This function is marked as + * never inlinable and placed into the normal text segment so that the + * call to the EEPROM function will be short even if the AUX boot section + * is used. + * + * \param[in] Address Address of the EEPROM location to write to + * \param[in] Data New data to write to the EEPROM location + */ +static void WriteEEPROMByte(uint8_t* const Address, + const uint8_t Data) +{ + eeprom_update_byte(Address, Data); +} + +/** Updates a FAT12 cluster entry in the FAT file table with the specified next + * chain index. If the cluster is the last in the file chain, the magic value + * \c 0xFFF should be used. + * + * \note FAT data cluster indexes are offset by 2, so that cluster 2 is the + * first file data cluster on the disk. See the FAT specification. + * + * \param[out] FATTable Pointer to the FAT12 allocation table + * \param[in] Index Index of the cluster entry to update + * \param[in] ChainEntry Next cluster index in the file chain + */ +static void UpdateFAT12ClusterEntry(uint8_t* const FATTable, + const uint16_t Index, + const uint16_t ChainEntry) +{ + /* Calculate the starting offset of the cluster entry in the FAT12 table */ + uint8_t FATOffset = (Index + (Index >> 1)); + bool UpperNibble = ((Index & 1) != 0); + + /* Check if the start of the entry is at an upper nibble of the byte, fill + * out FAT12 entry as required */ + if (UpperNibble) + { + FATTable[FATOffset] = (FATTable[FATOffset] & 0x0F) | ((ChainEntry & 0x0F) << 4); + FATTable[FATOffset + 1] = (ChainEntry >> 4); + } + else + { + FATTable[FATOffset] = ChainEntry; + FATTable[FATOffset + 1] = (FATTable[FATOffset] & 0xF0) | (ChainEntry >> 8); + } +} + +/** Updates a FAT12 cluster chain in the FAT file table with a linear chain of + * the specified length. + * + * \note FAT data cluster indexes are offset by 2, so that cluster 2 is the + * first file data cluster on the disk. See the FAT specification. + * + * \param[out] FATTable Pointer to the FAT12 allocation table + * \param[in] Index Index of the start of the cluster chain to update + * \param[in] ChainLength Length of the chain to write, in clusters + */ +static void UpdateFAT12ClusterChain(uint8_t* const FATTable, + const uint16_t Index, + const uint8_t ChainLength) +{ + for (uint8_t i = 0; i < ChainLength; i++) + { + uint16_t CurrentCluster = Index + i; + uint16_t NextCluster = CurrentCluster + 1; + + /* Mark last cluster as end of file */ + if (i == (ChainLength - 1)) + NextCluster = 0xFFF; + + UpdateFAT12ClusterEntry(FATTable, CurrentCluster, NextCluster); + } +} + +/** Reads or writes a block of data from/to the physical device FLASH using a + * block buffer stored in RAM, if the requested block is within the virtual + * firmware file's sector ranges in the emulated FAT file system. + * + * \param[in] BlockNumber Physical disk block to read from/write to + * \param[in,out] BlockBuffer Pointer to the start of the block buffer in RAM + * \param[in] Read If \c true, the requested block is read, if + * \c false, the requested block is written + */ +static void ReadWriteFLASHFileBlock(const uint16_t BlockNumber, + uint8_t* BlockBuffer, + const bool Read) +{ + uint16_t FileStartBlock = DISK_BLOCK_DataStartBlock + (*FLASHFileStartCluster - 2) * SECTOR_PER_CLUSTER; + uint16_t FileEndBlock = FileStartBlock + (FILE_SECTORS(FLASH_FILE_SIZE_BYTES) - 1); + + /* Range check the write request - abort if requested block is not within the + * virtual firmware file sector range */ + if (!((BlockNumber >= FileStartBlock) && (BlockNumber <= FileEndBlock))) + return; + + #if (FLASHEND > 0xFFFF) + uint32_t FlashAddress = (uint32_t)(BlockNumber - FileStartBlock) * SECTOR_SIZE_BYTES; + #else + uint16_t FlashAddress = (uint16_t)(BlockNumber - FileStartBlock) * SECTOR_SIZE_BYTES; + #endif + + if (Read) + { + /* Read out the mapped block of data from the device's FLASH */ + for (uint16_t i = 0; i < SECTOR_SIZE_BYTES; i++) + { + #if (FLASHEND > 0xFFFF) + BlockBuffer[i] = pgm_read_byte_far(FlashAddress++); + #else + BlockBuffer[i] = pgm_read_byte(FlashAddress++); + #endif + } + } + else + { + /* Write out the mapped block of data to the device's FLASH */ + for (uint16_t i = 0; i < SECTOR_SIZE_BYTES; i += 2) + { + if ((FlashAddress % SPM_PAGESIZE) == 0) + { + /* Erase the given FLASH page, ready to be programmed */ + BootloaderAPI_ErasePage(FlashAddress); + } + + /* Write the next data word to the FLASH page */ + BootloaderAPI_FillWord(FlashAddress, (BlockBuffer[i + 1] << 8) | BlockBuffer[i]); + FlashAddress += 2; + + if ((FlashAddress % SPM_PAGESIZE) == 0) + { + /* Write the filled FLASH page to memory */ + BootloaderAPI_WritePage(FlashAddress - SPM_PAGESIZE); + } + } + } +} + +/** Reads or writes a block of data from/to the physical device EEPROM using a + * block buffer stored in RAM, if the requested block is within the virtual + * firmware file's sector ranges in the emulated FAT file system. + * + * \param[in] BlockNumber Physical disk block to read from/write to + * \param[in,out] BlockBuffer Pointer to the start of the block buffer in RAM + * \param[in] Read If \c true, the requested block is read, if + * \c false, the requested block is written + */ +static void ReadWriteEEPROMFileBlock(const uint16_t BlockNumber, + uint8_t* BlockBuffer, + const bool Read) +{ + uint16_t FileStartBlock = DISK_BLOCK_DataStartBlock + (*EEPROMFileStartCluster - 2) * SECTOR_PER_CLUSTER; + uint16_t FileEndBlock = FileStartBlock + (FILE_SECTORS(EEPROM_FILE_SIZE_BYTES) - 1); + + /* Range check the write request - abort if requested block is not within the + * virtual firmware file sector range */ + if (!((BlockNumber >= FileStartBlock) && (BlockNumber <= FileEndBlock))) + return; + + uint16_t EEPROMAddress = (uint16_t)(BlockNumber - FileStartBlock) * SECTOR_SIZE_BYTES; + + if (Read) + { + /* Read out the mapped block of data from the device's EEPROM */ + for (uint16_t i = 0; i < SECTOR_SIZE_BYTES; i++) + BlockBuffer[i] = ReadEEPROMByte((uint8_t*)EEPROMAddress++); + } + else + { + /* Write out the mapped block of data to the device's EEPROM */ + for (uint16_t i = 0; i < SECTOR_SIZE_BYTES; i++) + WriteEEPROMByte((uint8_t*)EEPROMAddress++, BlockBuffer[i]); + } +} + +/** Writes a block of data to the virtual FAT filesystem, from the USB Mass + * Storage interface. + * + * \param[in] BlockNumber Index of the block to write. + */ +void VirtualFAT_WriteBlock(const uint16_t BlockNumber) +{ + uint8_t BlockBuffer[SECTOR_SIZE_BYTES]; + + /* Buffer the entire block to be written from the host */ + Endpoint_Read_Stream_LE(BlockBuffer, sizeof(BlockBuffer), NULL); + Endpoint_ClearOUT(); + + switch (BlockNumber) + { + case DISK_BLOCK_BootBlock: + case DISK_BLOCK_FATBlock1: + case DISK_BLOCK_FATBlock2: + /* Ignore writes to the boot and FAT blocks */ + + break; + + case DISK_BLOCK_RootFilesBlock: + /* Copy over the updated directory entries */ + memcpy(FirmwareFileEntries, BlockBuffer, sizeof(FirmwareFileEntries)); + + break; + + default: + ReadWriteFLASHFileBlock(BlockNumber, BlockBuffer, false); + ReadWriteEEPROMFileBlock(BlockNumber, BlockBuffer, false); + + break; + } +} + +/** Reads a block of data from the virtual FAT filesystem, and sends it to the + * host via the USB Mass Storage interface. + * + * \param[in] BlockNumber Index of the block to read. + */ +void VirtualFAT_ReadBlock(const uint16_t BlockNumber) +{ + uint8_t BlockBuffer[SECTOR_SIZE_BYTES]; + memset(BlockBuffer, 0x00, sizeof(BlockBuffer)); + + switch (BlockNumber) + { + case DISK_BLOCK_BootBlock: + memcpy(BlockBuffer, &BootBlock, sizeof(FATBootBlock_t)); + + /* Add the magic signature to the end of the block */ + BlockBuffer[SECTOR_SIZE_BYTES - 2] = 0x55; + BlockBuffer[SECTOR_SIZE_BYTES - 1] = 0xAA; + + break; + + case DISK_BLOCK_FATBlock1: + case DISK_BLOCK_FATBlock2: + /* Cluster 0: Media type/Reserved */ + UpdateFAT12ClusterEntry(BlockBuffer, 0, 0xF00 | BootBlock.MediaDescriptor); + + /* Cluster 1: Reserved */ + UpdateFAT12ClusterEntry(BlockBuffer, 1, 0xFFF); + + /* Cluster 2 onwards: Cluster chain of FLASH.BIN */ + UpdateFAT12ClusterChain(BlockBuffer, *FLASHFileStartCluster, FILE_CLUSTERS(FLASH_FILE_SIZE_BYTES)); + + /* Cluster 2+n onwards: Cluster chain of EEPROM.BIN */ + UpdateFAT12ClusterChain(BlockBuffer, *EEPROMFileStartCluster, FILE_CLUSTERS(EEPROM_FILE_SIZE_BYTES)); + + break; + + case DISK_BLOCK_RootFilesBlock: + memcpy(BlockBuffer, FirmwareFileEntries, sizeof(FirmwareFileEntries)); + + break; + + default: + ReadWriteFLASHFileBlock(BlockNumber, BlockBuffer, true); + ReadWriteEEPROMFileBlock(BlockNumber, BlockBuffer, true); + + break; + } + + /* Write the entire read block Buffer to the host */ + Endpoint_Write_Stream_LE(BlockBuffer, sizeof(BlockBuffer), NULL); + Endpoint_ClearIN(); +} |